Instantaneous water-heater.



C. A. BACKSTROM.

INSTANTANEOUS WATER HEATER.

APPLICATION FILED AUG-3. ISIS.

1 QQSIYSUQ Patented Apr. 23, 1918.

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, MI M ATTORNEYS.

C. A. BACKSTROIVL INSTANTANEOUS WATER HEATER.

APPLICATION FILED M63. 1915.

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G. A. BACKSTROM.

lNSTANTANEOUS WATER HEATER.

APPLICATION FILED AUG-3 9]5- M Eatented Apr. 23, 1918.

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WITNESS:

ATTORNEYS.

CHARLES A. BACKSTROM, 0F GRAFTON, PENNSYLVANIA, ASSIGNON TO PITTEBUNG WATER HEATER COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CQRJPOATTUN OF N JEW JERSEY.

INSTANTANEOUS WATER-HEAT.

' Patented Apr. 23, TFT

Application filed August 3, 1915. serial No. $5,401.

To all whom it may concern:

Be it known that T, CHARLES A. Bequs'rRoM, a citizen of the United States, residing at Grafton, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Tnstantaneous Water-Heaters, of which the following is a specification.

The invention relates to water heaters and more particularly to those known as instantaneous heaters, although the thermostatic controlling means is useful in connection with other types such as storage heaters in which a quick opening and closing of the gas valve is desirable. The primary objects of the invention are; the provision, of a thermostatic control which shall be quick acting and sensitive, thus giving close regulation and increased economy of operation; the provision of a control in which the strain imposed onthe thermostat multiplying device is reduced to a minimum so that these parts are not liable to a shift in adjustment due to the strain im osed thereon and may be made relatively ight; the provision of a construction in which the work imposed on the thermostatically controlled parts in closing the valve is reduced to a minimum so that slow action and danger of sticking is avoided; the provision of an improved thermostatic multiplying device and the means for securing its adjustment; and in general the provision of an improved and simplified thermal controlling means for instantaneous and storage heaters. Certain embodiments of the invention are illustrated in the accompanying drawings, wherein Figure 1 is a partial side elevation and partial section showing the application of my invention to a water heater, Fig. 2 is a vertical section showing a part of the mechanism of Fig. 1 on an enlarged scale, Fig.

3 is a partial side elevation and partial section of a modification, and Figs. 4 and 5 are sectional views illustrating other modifications.

Referring to the general arrangement as shown in Fig. 1; 1 is the casing of the heater, 2 is the water container in the form of a coil having its inlet at 3; 4 is the thermostat casing having an inlet from the coil 2 at 5 and an outlet leading to the hot water taps or spigots; 7 is the gas valve having an inlet at 8 and an outlet at 9; 10 is the gas supply pipe leading from the outlet 9 to 13 is a water motor or watenvalve, as it is commonly called, which serves to automatically 0 en the gas valve when the outlet from t e heater is open, such water valve belng provided with a piston 14: which moves down when the outlet from the heater 1s opened thus relieving the pressure on the lower side of the piston.

My invention relates particularly to the mechanism for controlling the gas valve 12 both from the water motor and from the thermostat, and this mechanism will be best understood by reference to Fig. 2 which shows the parts on an enlarged scale. The water valve piston 14 carries the stem 15 and when the outlet from the heater is closed this stem is held in the position indicated in Figs. 1 and 2 by means of the spring 16 which engages thecollar 17 screwthreaded upon the stem. It will be understood that when the outlet from the heater is opened the stem 15 moves down by reason of the unbalanced water pressure in the casing 13, and that when the outlet from the heater is closed and the water pressure in the casing 13 becomes balanced the spring 16 causes the stem to move upward to the position illustrated. The thermostat in the casing 4:

consists of a tube 18 of copper or similar in the casing 18. This plug carries an oper- 'ating pin 22 preferably of hardened steel.

Mounted in the gas valve casing 7 and interposed between the gas valve 12 and the operating pin 22 is a multiplying device for securing the requisite amount of movement in the gas valve. This multiplying device is mounted upon a support or frame 23 having its right hand end 24 in the coupling 25 and its left hand end 26 fitting into the screw plug 27. The left hand end of the frame is held in the screw plug by means of the threaded rod 28, the screw plug being locked in position by means of the lock nut 29, and the rod by means of the lock nut 30. The plug and rod together constitute an adjusting means for the thermostat as the position of the multiplying levers can be changed with respect to the pin 22, thus giving an earlier or later closure of the valve as conditions may require. The plug and rod are covered by means of a cap 31 held in position by means of the nut 32. The multiplying arrangement consists of the two levers 33 'and34 pivoted at 35 and 36 re-.

spectively, to the framework and the link 37 connecting the two levers. The lever 34 is moved up to cause the closure of the valve 12 by means of the spring 38 mounted upon the rod 39 whose lower end is screwthreaded into the frame 23, and whose upper end serves as a guide for the forked end of the lever 34. It will be seen that as the water in the heater becomes hotter and the tube 18 moves to the right, thus permitting the pin 22 to move to the right, the levers are released from the action of the pin so that the spring 38 can move the lever 34 upward thus closing the gas valve. The movement of the porcelain rod and the plug 21 and pin 22 carried thereby to the right is assisted by means of the relatively stifi' spring 40 interposed between the plug 21 and the boss 24.

The valve 12 is provided with a leather or similar packing member 41 held in position by the cap 42, the parts 12 and 42 being made hollow to provide a space for the spring 43 and the end of the stem 44 which stem is provided with a collar 45 bearing against the upper end of the spring 43. The valve will open by gravity when the collar 45 moves down, so that the spring 43 may be made very light or dispensed with, serving primarily to provide a small amount of power to detach the valve in case the leather sticks to the valve seat. When the water in the heater is cold and no water is flowing therefrom, the stem 44 serves to hold the gas valve closed, this action being secured by reason of the relatively stifl spring 46 bearing at its upper end upon the collar 4.7 carried by the stem 44 and guided in the tube 48 which extends from the gas valve casing to the fork 49 in which the water valve spring 16 is mounted. The lower end of the water valve stem 15 is provided with a nut 50 also guided in the tube 48 in opposition to the gas valve stem 44, a space being preferably left between the opposing ends of the two stems so that slight accidental movements of the water valve piston will not cause an opening of the gas valve.

The operation of the apparatus is as follows, the water in the heater being cold.

Upon opening a tap or spigot leading from the thermostat casing, the pressure upon the lower side of the water valve piston 14 is reduced and such piston moves downward, and the lower end of the water valve stem 15 engages the end of the gas valve stem 44 opening the gas valve 12 and permitting gas to flow through the casing 7 from the inlet pipe 8 to the pipe 10 leading to the burners 11. The parts remain in this position until the water becomes heated above a certain point when the expansion of the thermostat tube 18 permits the rod 19 and pin 22 to move to the right under the influence of the spring 40. The retraction of the P111 22 permits the spring 38 to move the lever 34 upward to engage the projection 51 on the lower side of the gas valve and move it quickly to closed position, thus throttling the supply of gas. If, while the gas valve is open, the outlet from the heater-be closed, the pressure in the water valve casing 13 Wlll become equalized and the spring 16 will move the piston and stem 15 upward, thus releasing the upper end of the gas valve stem 44. When the gas valve stem is released the spring 46 will move the stem upward until the collar 45 closes the gas valve.

If the water motor piston 14 should accidentally become stuck when in its lower position so that the spring 16 cannot move it upward when the outlet from the heater is closed, the thermostat can still close the gas valve because of the slip connection between the stem 44 and the gas valve. That 1s, the upward movement of the lever34 under the influence of the spring 38 will cause the valve to move upward with respect to the collar 45 and stem 44' and seat, the spring 43 which resists this upward movement being relatively weak as compared with the spring 38.

The apparatus as above described has certain advantages s compared with the prior art structures for accomplishing the same general function of the dual control of the gas valve frOm the water motor and from the thermostat. One of these advanta es is ncident to the use of the sprin 40 (Fig. 2) 1n addition to the spring 38. Tf the spring 40 were not employed the spring 38 would.

have to be made relatively much stronger 1n order to push the porcelain rod to the right and this would throw much additional stram on the multiplying device tending to throw the parts-out of adjustment and make the action sluggish. Since the spring 40 acts independently of the multiplying device and performs the work of causing the porcelain rod to follow the movement of the expanslble rod 18 to the right, the only work thrown upon the spring 38 is that of moving the multiplying levers and of closmg the valve 12. This spring can therefore be made relatively weak and the multiplying levers can be'made very light. This makes the device operate more quickly and the parts will work for an indefinite period wlthout getting out of adjustment since the strain lmposed on the parts is so slight. It Wlll also be noted that the thermostatic part can act to close the valve without causing the movement of any gas valve stem or similar part through a stuffing box, this advantage being due to the fact that the parts are contained in the casing 7 and to the fact that the slip connection is provided between the gas valve and the stem 44, so

that the closure of the valve does not necessitate the movement of the stem. The danger of the pats sticking and thus preventing the closure of the valve under thermostatic 10 action is reduced to a mlIHIIlllIIl.

the adjustment necessary to secure the proper point of cut-olf afterward very easily made when the device is inserted 1nto the gas valve casing. Various other advantages incident to the simplicity of the devlce and the cheapness of its constructlon W111 be readily apparent to those skilled 1n the art. Fig. 3 illustrates a modified construction in which the thermostat caslng 52 1s arranged vertically and external of the heater casing, and the multlplylng arrangement between the thermostat and the gas valve is mounted upon a frame 53 which is adjustable, the construction being the same as 1n the other type of construction. The therinostat is also imilar to that of the other type of construction except that the parts are arranged vertically. These parts consist of the expansible tube 56 and the porcelain rod 57 for operating the pin 58, a sprlng 60 being employed and performing the function of the spring 40 of the other type of construction. The pin 58 operates through the levers 61 and 62 and the link 63, a spring 64 being provided for lifting the lever 62 and closing the gas valve 65. The gas valve is provided with a stem 66 havmg a slip connection with the valve just as in the other type of construction the stem being normally held in its uppermost position bymeans of a spring 7 6 corresponding to the sprlng 46 of the other type of construction. The water motor comprises a casing 68 carrying a piston (not shown) to which is attached the stem 69. The piston is moved to its lower position when the outlet from the heater is opened and moved back to its upper position by means of a spring located inside the casing 68. The similarity of the whole contruction to that of the previously described construction is such that any description of the operation is unnecessary.

Fig. 4 illustrates another modlfication which differs from the construction heretofore described in that the spring in the h0l low gas'valve 70 is removed and placed above the gas valve as indicated at 71. The rest of the construction including the casing 72, stem 73, and the collar 74 is the same as in the other construction.

Fig. 5 illustrates still another modification llltlt in which the spring acting to open the gas valve 75 is entirely eliminated, the valve preferably being made a little heavier and opening entirely by gravity. The casing 76, the stem 77, and the collar 78 are the same as in the other constructions, the springs in the ether types of constructions being used, as heretofore pointed out, to insure the opening of the valve if the force of gravity is not sufficient, and this is accomplished in the construction of Fig. 5 by increasing the weight of the valve.

What I claim is:

1. In-combination in a water heater, a water container, a gas burner, a conduit for supplying gas to the burner, a gas valve in the conduit arranged to be yieldingly maintained in open position when not acted upon externally, a thermostat comprising a plurality of elements, a multiplying device between one of the thermostat elements and valve arranged to yieldingly close the valve when the water rises above a certain temperature, but held by. the thermostat element from closing the valve when the water is below said certain temperature, and a spring 'acting independently of the multiplying device for retracting the said thermostatic element as the water is heated.

2. In combination in a water heater, a water container, a gas burner, a conduit for supplying gas to the burner, a gas valve in the conduit arranged to be yieldingly maintained in open position when not acted upon externally a thermostat comprising a relatively expansible element and a relatively non-expansible element moved by the expansible element in one direction but not in the reverse direction, a multiplying device between the non-expansible element and the valve having means to yieldingly close the gas valve, but restrained from such action by said non-expansible element-when the water is below a certain temperature, and a spring acting independently of the multiplying device to cause the said nonexpansible element to follow the reverse movement of the expansible element as the temperature of the water rises.

3. In combination in a waterheater, a water container, a gas burner, a conduit for supplying gas to the burner, a gas valve in the conduit arranged to be yieldingly maintained in open position when not acted upon externally, a thermostat comprising a relatively expansible element and a relatively non-expansible element moved by the expansible element in one direction but not in the reverse direction, a multiplying device between the non-expansible element and the & v

plying device to cause the said non-expansible element to follow the reverse movement of the expansible element as the temperature of the water rises.

4. In combination in a water heater, a water container, a burner, a conduit for supplying gas to the burner,a gas valve in the conduit which yieldingly opens when not acted upon externally, a stem having a slip connection with the valve, a spring out side the conduit for maintainlng the stem in operative engagement with the valve to hold such valve closed, a thermostat, a yielding means controlled by the thermostat for closing the valve when the temperature of the water rises above a certain point, and a water motor operated by the opening and closing of the outlet from the heater and arranged, when the outlet is opened, to move the said stem to release position with respect to the gas valve, and permit such valve to open.

5. In combination in a water heater, a water container, a burner, a conduit for supplying gas to the burner, a gas valve in the conduit which yieldingly opens when not acted upon externally, a stem having a slip connection with the valve, a spring carried in the valve and tending to prevent the stem moving at said slip connection relatively to the valve, a spring outside the conduit for maintaining the stem in operative engagement with the valve to hold such valve closed, a thermostat, a yielding means controlled by the thermostat for closing the not acted upon externally, a spring having a slip connection with the valve for holding the gas valve closed, a thermostat compris- -ing a relatively expansible element and a relatively non-expansible element moved by the expansible element in one direction but not in the reverse direction, a multi lying device between the non-expansible e ement and the valve having means to yieldingly close the gas valve, but restrained from such action by said non-expansible element when the water is below a certain temperature, a spring acting independently of the multiplying device to cause the said non-expansible element to follow the reverse movement of the expansible element as the temperature of the water rises, and a water motor operated by the opening and closing of the outlet from the heater and arranged, when the outlet is opened, to release the said spring for holding the gas valve closed and the slip connection and permit the gas valve to Open CHAS. A. BACKSTROM. 

